Deciding factor for me was cost, both were free, LOL.
One was in a bait shop for decades, took some " deodorizing", once I scraped the grey gunk out of the bottom. And that was the pick.of the litter, gave the other 2 to friends.
Bigger is always better IF you have need for it. Freezers are most efficient when full of frozen goods. Chests more efficient but have the notorious tendency to bury the unknown frozen down below, uprights not such much.
If I had my druthers I would have both. Chest for longer term storage such as bulk frozen garden veggies and meat an upright in the kitchen or close to for immediate use items. With a regular routine of pulling from the chest to the upright to avoid the forgotten frozen.
Or at least that's what I do with my chest and fridge freezer.
I organize all my meat in milk crates and keep a "map" of contents and dates on cardboard in the crate. New meat goes on bottom and bottom crate moved to top.
Have and upright and chest freezer in the basement for the normal stuff. Shot 3 deer last fall and had no room in either. Bought a 10 cu.ft chest in put it in my unheated shop. Had plenty of room for the 3 deer and even put two 24lb turkeys and three 18lb turkeys in it. Make sure whatever you buy that it is guaranteed to continue working at 0 degrees or lower. Too many folks end up buying a freezer that will only operate at temperatures above freezing. Below freezing temperatures compressor/cooling unit the stops working, and never works again. Have friends learn that lesson the hard/expensive way!
I took some of your advice. I went to Lowes to buy a freezer. The stand up freezers were $1000! We bought the 7.7 cubic ft. chest freezer. Its perfect!
I grind about all my meat. Usually 5-6 per year. We vacuum seal. No problems within two years in a frost free upright, or a chest.
having 2 chest freezers and an upright I don't always get to the bottom of them very often . I was doing a little cleaning in 2020 and found some 2016 vacuum packed ground venison and it was just fine when we ate it,
Have one of each and I'll never own another chest style. No doubt in my mind they have contributed to a huge amount of wasted food that gets buried and forgotten about for the next 10 years. My wife is 4'-10", ask her which one she absolutely hates lol....